22 Apr, 2014

Simple Equations to Approximate Changes to the Properties of Crude Oil with Changing Temperature

This article describes simple equations to approximate changes to the properties of crude oil with changing temperature. Changes in crude oil density and specific heat, or heat capacity, can be estimated from graphs and/or more elaborate computer simulation. The latter generally requires access to a process simulator and characterization data for the crude oil. A suitable, tuned computer model is likely the most accurate method of estimating the fluid properties, but is not always available. Direct laboratory measurement is also possible if facilities and oil samples are available and a high degree of accuracy is required.

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11 Feb, 2014

Acid Gas-Water Content

This post goes over the acid gas-water phase behavior system. Specifically, different methods of predicting water content of acid gas systems are evaluated based on experimental data from the literature. Water content diagrams compatible with the experimental data for pure CO2, Pure H2S, pure CH4 and their mixtures are generated and presented. These charts can be used for facility type calculations and trouble shooting.

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16 Dec, 2013

Estimating TEG Vaporization Losses in TEG Dehydration Unit

In this Tip of The Month (TOTM), the effect of striping gas rate and triethylene glycol (TEG) circulation ratio on the TEG vaporization loss from the regenerator top and contactor top is investigated. Specifically, this study focuses on the variation of TEG vaporization losses with reboiler pressure, TEG circulation ratio and stripping gas rate. By performing a rigorous computer simulation of TEG regeneration at reboiler pressures of 110.3 kPaa (16 psia) and 524.1 kPaa (76 psia), several charts for quick estimation of TEG vaporization losses from regenerator top and contactor, which are needed for facilities type calculations are developed. In addition, the effect of contactor temperature on the TEG vaporization losses for a case study is shown.

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7 Nov, 2013

Estimating Still Column Top Temperature in TEG Dehydration Unit

In this Tip of The Month (TOTM), the effect of striping gas rate and TEG circulation ratio on the still column top temperature for regeneration of rich triethylene glycol (TEG) is investigated. Specifically, this study focuses on the variation of still column top temperature with reboiler pressure, TEG circulation ratio and stripping gas rate. By performing a rigorous computer simulation of TEG regeneration at reboiler pressures of 110.3 kPaa (16 psia) and 524.1 kPaa (76 psia), two charts for quick determination of still column top temperature needed for facilities type calculations are developed. In addition, the effect of theoretical number of trays in the stripping gas section is studied.

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4 Oct, 2013

The Stainless Steel Family - An Overview

Stainless steel is a family of corrosion resistant steels containing chromium in which the chromium forms a passive film of chromium oxide (Cr2O3) when exposed to oxygen [1]. This phenomenon is called passivation and is seen in other metals, such as aluminium and titanium. The film layer is impervious to water and air and quickly reforms when the surface is scratched. This protects the metal beneath – preventing further surface corrosion. Since the layer only forms in the presence of oxygen, corrosion-resistance can be adversely affected if the component is used in a non-oxygenated environment e.g. underwater bolts on a platform support structure.

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11 Sep, 2013

High Pressure Regeneration of TEG with Stripping Gas

In this article, regeneration of rich triethylene glycol (TEG) with striping gas at high pressure is investigated. Specifically, this study focuses on the determination of the required stripping gas rate as a function of the lean TEG mass percent, reboiler temperature, and the number of theoretical trays in the stripping section (NS) for a regenerator (still) column with two theoretical trays (NR). By performing rigorous computer simulations of TEG regeneration at high pressure, a series of charts for quick determination of stripping gas rates needed for facilities type calculations are developed.

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